What is the treatment for pseudotumor (idiopathic intracranial hypertension)?

Treatment of Pseudotumor Cerebri (Idiopathic Intracranial Hypertension)

The treatment of pseudotumor cerebri (idiopathic intracranial hypertension) should follow a stepwise approach starting with weight loss for overweight patients, acetazolamide as first-line medical therapy, and surgical interventions for cases with severe or progressive visual loss. 1, 2

Diagnosis and Initial Assessment

• MRI of the brain and orbits is the most useful initial imaging modality for evaluating patients with suspected pseudotumor cerebri 3, 1
• CT venography (CTV) or MR venography (MRV) should be performed to evaluate cerebral venous sinuses and exclude thrombosis 1, 2
• Diagnostic criteria include papilledema, normal neurological examination, normal brain parenchyma on imaging, normal CSF composition, and elevated lumbar puncture opening pressure 1, 4

Treatment Algorithm

Step 1: Weight Management (First-line)

• Weight loss is the first-line treatment for pseudotumor cerebri in overweight patients 1, 5
• Target 5-15% weight loss, which has been shown to put IIH into remission 2, 5
• Refer to community or hospital-based weight management programs 2
• Consider bariatric surgery for appropriate candidates who need sustained weight loss 2, 5

Step 2: Medical Management

• Acetazolamide is the first-line medication for patients with mild visual loss 1, 5
  • Start at a lower dose and gradually increase as needed and tolerated 1
• Topiramate may be considered as an alternative, as it helps with weight loss through appetite suppression and reduces intracranial pressure through carbonic anhydrase inhibition 1, 4
• Zonisamide may be an alternative where topiramate has excessive side effects 1
• Identify and discontinue medications that might cause or exacerbate IIH (tetracyclines, vitamin A, retinoids, steroids, growth hormone, thyroxine, and lithium) 1, 4

Step 3: Surgical Management

• Urgent surgical intervention is required for patients with:

  • Imminent risk of visual loss 2
  • Rapidly progressive visual decline 2, 6
  • Failure of medical management 5, 6

• Surgical options include:

  • Ventriculoperitoneal (VP) shunt - preferred CSF diversion procedure due to lower revision rates 1, 2
  • Optic Nerve Sheath Fenestration (ONSF) - effective and safe procedure with fewer complications than CSF diversion procedures 1, 6
  • Neurovascular stenting - may lead to improvement in symptoms but has potential complications 1, 7
  • Temporizing lumbar drain may protect vision while planning definitive surgery 2

Monitoring and Follow-up

• Regular ophthalmologic assessments to monitor papilledema and visual function 2, 5
• Be aware of treatment failure rates: worsening vision after stabilization in 34% of patients at 1 year and 45% at 3 years 1, 4
• Failure to improve headache occurs in one-third to one-half of treated patients 1
• Once papilledema has resolved, hospital-based visual monitoring may no longer be required, but caution is needed for asymptomatic patients who may remain asymptomatic during recurrence 1

Important Considerations and Pitfalls

• Serial lumbar punctures are not recommended for long-term management of IIH 1
• ONSF should be performed only by an experienced clinician trained in this technique 1
• CSF shunting exclusively to treat headache has limited evidence, with 68% of patients continuing to have headaches at 6 months 1
• Patients with IIH often develop migrainous headaches superimposed on headaches from raised intracranial pressure, requiring specific treatment approaches 1, 4
• Secondary causes of pseudotumor cerebri should be thoroughly investigated, especially in non-obese patients 2, 4